Align selected nodes with center anchor globally or selected nodes’ center locally. Normally, the center anchor(a Triangle) is not show up, you can turn on the Part Mirror to make it visible, then turn Part Mirror off, the center anchor would not gone once showed.

Usually, you will no need to use this, because the Rendered Model always show. But if you can not find the Rendered Model and you are sure the generation is done, then maybe it goes to some weird position, you can use this menu item to reset it’s position.